Conventionally, in the production of semiconductor devices, microfabrication by lithography using a photoresist has been performed. The microfabrication is a processing method for forming fine convexo-concave shapes corresponding to the following pattern on the surface of a substrate by: forming a thin film of a photoresist on a semiconductor substrate such as a silicon wafer; irradiating the resultant thin film with an active ray such as an ultraviolet ray through a mask pattern in which a pattern of a semiconductor device is depicted for development; and subjecting the substrate to etching processing using the resultant photoresist pattern as a protecting film. Recently, however, the high integration of semiconductor devices has progressed and the adopted active ray tends to have a shorter wavelength, such as an ArF excimer laser (193 nm) replacing a KrF excimer laser (248 nm). Following such a tendency, the influence of reflection of an active ray on a semiconductor substrate has become a large problem.
In addition, as an underlayer film between the semiconductor substrate and the photoresist, the use of a film known as a hard mask containing a metal element such as silicon and titanium (see, for example, Patent Document 1) is performed. In this case, the resist and the hard mask have components largely different from each other, so that the removal rates of the resist and the hard mask by dry etching largely depend on the type of a gas used for dry etching. Then, by appropriately selecting the type of a gas, the hard mask can be removed by dry etching without a large decrease in the film thickness of the photoresist. Thus, in the production of semiconductor devices in recent years, for achieving various effects such as the reflection preventing effect, a resist underlayer film has become disposed between the semiconductor substrate and the photoresist. Then, also until today, the studies of a composition for a resist underlayer film have been performed, however, due to the diversity of characteristics required for the composition and the like, the development of a novel material for the resist underlayer film is desired.
As an underlayer film between the semiconductor substrate and the photoresist, the use of a film known as a hard mask containing a metal element such as silicon and titanium (see, for example, Patent Document 1) is performed. In this case, the resist and the hard mask have components largely different from each other, so that the removal rates of the resist and the hard mask by dry etching largely depend on the type of a gas used for dry etching. Then, by appropriately selecting the type of a gas, the hard mask can be removed by dry etching without a large decrease in the film thickness of the photoresist. Thus, in the production of semiconductor devices in recent years, for achieving various effects such as the reflection preventing effect, a resist underlayer film has become disposed between the semiconductor substrate and the photoresist. Then, also until today, the studies of a composition for a resist underlayer film have been performed, however, due to the diversity of characteristics required for the composition and the like, the development of a novel material for the resist underlayer film is desired.
There is disclosed a composition using a compound having a silicon-silicon bond or a pattern forming method using the composition (see, for example, Patent Document 2).
On the other hand, there is also disclosed a coating agent using a polysiloxane material having a sulfide group (see, for example, Patent Document 3 and Patent Document 4).
There is disclosed an application of a polysiloxane material having a sulfide bond to a lithography process (see Patent Document 5).